When warning about unsafe uses of dispatch_once, specially handle the

crazy case where dispatch_once gets redefined as a macro that calls
_dispatch_once (which calls the real dispatch_once).  Users want to
see the warning in their own code.

Fixes <rdar://problem/11617767>

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@163816 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 15 insertions, 0 deletions

diff --git a/test/Analysis/unix-fns.c b/test/Analysis/unix-fns.c
index ec620985d9..f9c052e165 100644
--- a/test/Analysis/unix-fns.c
+++ b/test/Analysis/unix-fns.c
@@ -136,3 +136,18 @@ void test_valloc_nowarn(size_t sz) {
     foo[i] = 0;
   }
 }
+
+// Test dispatch_once being a macro that wraps a call to _dispatch_once, which in turn
+// calls the real dispatch_once.
+
+static inline void _dispatch_once(dispatch_once_t *predicate, dispatch_block_t block)
+{
+  dispatch_once(predicate, block);
+}
+
+#define dispatch_once _dispatch_once
+
+void test_dispatch_once_in_macro() {
+  dispatch_once_t pred = 0;
+  dispatch_once(&pred, ^(){});  // expected-warning {{Call to 'dispatch_once' uses the local variable 'pred' for the predicate value}}
+}